Electromagnetic machines such as electric motors, generators, and traction motors are useful for converting energy from one form to another. Such electromagnetic machines often include an element rotatable about an axis. The rotatable element or rotor may be coaxial with a static element or stator, and energy may be converted via relative rotation between the rotor and the stator.
One type of electromagnetic machine, an alternating current induction motor, uses induced current flow to magnetize portions of the rotor during motor operation. More specifically, induced current may flow through conductor bars disposed parallel or nearly parallel to the axis along a periphery of the rotor. Each conductor bar may be electrically connected to every other conductor bar by two shorting rings disposed at opposite ends of the rotor. The shorting rings and conductor bars are subject to inertial forces during rotor operation.